Thin film magnetic head and method of manufacturing same

ABSTRACT

It is an object to provide a thin film magnetic head which can precisely control a throat height of a recording head. A bottom pole of the recording head is divided into a bottom pole tip and a bottom pole layer, and the bottom pole tip is formed having a convex shape on a flat surface of the bottom pole layer. Insulating layers formed with inorganic materials, along with a first layer of the thin film coil are buried in a concave region between the bottom pole tip and a bottom connecting portion. The throat height is determined by an edge frame (that is, an edge frame of the opposite side of a track surface of the bottom pole tip) of a bottom-pole-tip side of the insulating layers. As a result, unlike a photoresist film of a related art, a pattern shift of the edge frame and deterioration of profile can be avoided, and the throat height can be precisely controlled.

BACKFGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a thin film magnetic head havingat least an inductive-type magnetic transducer for writing and a methodof manufacturing the same.

[0003] 2. Description of the Related Art

[0004] Performance improvement in thin film magnetic heads has beensought in accordance with an increase in surface recording density of ahard disk device. A composite thin film magnetic head, which is made ofa layered structure including a recording head having an inductive-typemagnetic transducer for writing and a reproducing head havingmagnetoresistive (MR) elements for reading, is widely used as a thinfilm magnetic head. The MR elements includes an anisotropicmagnetoresistive (AMR) element that utilizes the AMR effect and a giantmagnetoresistive (GMR) element that utilizes the GMR effect. Areproducing head using an AMR element is called an AMR head or simply anMR head. A reproducing head using the GMR element is called a GMR head.The AMR head is used as a reproducing head whose surface recordingdensity is more than 1 gigabit per square inch. The GMR head is used asa reproducing head whose surface recording density is more than 3gigabit per square inch.

[0005] In general, an AMR film is made of a magnetic substance thatexhibits the MR effect and has a single-layered structure. In contrast,most of GMR films have a multi-layered structure consisting of aplurality of films. There are several types of mechanisms which producesthe GMR effect. The layer structure of a GMR film depends on themechanism. The GMR films include a super-lattice GMR film, a spin valvefilm, a granular film and so on, while the spin valve film is mostefficient as the GMR film which has a relatively simple structure,exhibits a great change in resistance in a low magnetic field, and issuitable for mass reproduction.

[0006] As a primary factor for determining the performance of areproducing head, there is a pattern width, especially an MR height. TheMR height is the length (height) between the end of an MR element closerto an air bearing surface and the other end. The MR height is originallycontrolled by an amount of grinding when the air bearing surface isprocessed. The air bearing surface (ABS) here is a surface of a thinfilm magnetic head that faces a magnetic recording medium and is alsocalled a track surface.

[0007] Performance improvement in a recording head has also beenexpected in accordance with the performance improvement in a reproducinghead. It is required to increase the track density of a magneticrecording medium in order to increase the recording density among theperformance of a recording head. In order to achieve this, a recordinghead of a narrow track structure in which the width of a bottom pole anda top pole sandwiching a write gap on the air bearing surface isrequired to be reduced to the order of some microns to submicron.Semiconductor process technique is used to achieve the narrow trackstructure.

[0008] Another factor determining the performance of a recording head isthe throat height (TH). The throat height is the length (height) of aportion (magnetic pole portion) which is from the air bearing surface toan edge of an insulating layer which electrically isolates the thin filmcoil. Reducing the throat height is desired in order to improve theperformance of a recording head. The throat height is controlled as wellby an amount of grinding when the air bearing surface is processed.

[0009] In order to improve the performance of a thin film magnetic head,it is important to form the recording head and the reproducing head asdescribed in well balance.

[0010] Here, an example of a manufacturing method of a composite thinfilm magnetic head as an example of a thin film magnetic head of arelated art is to be described with reference to FIGS. 31A and 31B toFIGS. 36A and 36B.

[0011] As shown in FIGS. 31A and 31B, an insulating layer 102 made of,for example, alumina (aluminum oxide, Al₂O₃ of about 5 to 10 μm inthickness is formed on a substrate 101 made of, for example, aluminumoxide and titanium carbide (Al₂O₃-TiC). Further, a bottom shield layer103 for a reproduction head made of, for example, permalloy (NiFe) isformed on the insulating layer 102.

[0012] Next, as shown in FIGS. 32A and 32B, for example, alumina ofabout 100˜200 nm in thickness is deposited on the bottom shield layer103 to form a shield gap film 104. Then, an MR film 105 of tens ofnanometers in thickness for making up the MR element for reproduction isformed on the shield gap film 104, and photolithography with highprecision is applied to obtain a desired shape. Next, a lead terminallayer 106 facing the MR film 105 is formed by lift-off method. Next, ashield gap film 107 is formed on the shield gap film 104, the MR film105 and the lead terminal layer 106, and the MR film 105 and the leadterminal layer 106 are buried in the shield gap layers 104 and 107.Next, a top shield-cum-bottom pole (called bottom pole in thefollowings) 108 of about 3 μm in thickness made of, for example,permalloy (NiFe), which is a material used for both of a reproductionhead and a recording head, is formed on the shield gap film 107.

[0013] Next, as shown in FIGS. 33A and 33B, a write gap layer 109 ofabout 200 nm in thickness made of an insulating layer such as an aluminafilm is formed on the bottom pole 108. Further, an opening 109 a forconnecting the top pole and the bottom pole is formed through patterningthe write gap layer 109 by photolithography. Next, a pole tip 110 isformed with magnetic materials made of permalloy (NiFe) and nitrideferrous (FeN) through plating method, while a connecting portion pattern110 a of the top pole and the bottom pole is formed. The bottom pole 108and a top pole layer 116 which is to be described later are connected bythe connecting pattern 110 a and so that forming a through hole afterCMP (Chemical and Mechanical Polishing) procedure which is to bedescribed later becomes easier.

[0014] Next, as shown in FIGS. 34A and 34B, the write gap layer 109 andthe bottom pole 108 are etched about 0.3˜0.5 μm by ion milling havingthe pole tip 110 as a mask. By etching the bottom pole 108, a trimstructure is formed. As a result, widening of effective write trackwidth can be avoided (that is, suppressing widening of magnetic flux atthe bottom pole when data is being written). Next, after an insulatinglayer 111 of about 3 μm, made of, for example, alumina is formed allover the surface, the whole surface is flattened by CMP.

[0015] Next, as shown in FIGS. 35A and 35B, a first layer of a thin filmcoil 112 for inductive-type recording heads made of, for example, copper(Cu) is selectively formed on the insulating layer 111 by, for example,plating method. Further, a photoresist film 113 is formed in a desiredpattern on the insulating layer 111 and the thin film coil 112 byphotolithography with high precision. Further, a heat treatment ofdesired temperature is applied for flattening the photoresist film 113and insulating between the thin film coils 112. Likewise, a second layerof a thin film coil 114 and a photoresist film 115 are formed on thephotoresist film 113, and a heat treatment of desired temperature isapplied for flattening the photoresist film 115 and insulating betweenthe thin film coils 114.

[0016] Next, as shown in FIGS. 36A and 36B, a top pole yoke-cum-top polelayer (called a top pole layer in the followings) 116 made of, forexample, permalloy, which is a magnetic material for recording heads, isformed on the top pole 110, the photoresist films 113 and 115. The toppole layer 116 has a contact with the bottom pole 108 in a position rearof the thin film coils 112 and 114, and is magnetically coupled to thebottom pole 108. Further, an over coat layer 117 made of, for example,alumina is formed on the top pole layer 116. At last, a track surface(air bearing surface) of recording heads and reproducing heads is formedthrough a slider machine processing, and a thin film magnetic head iscompleted.

[0017] In FIGS. 36A and 36B, TH represents the throat height and MR-Hrepresents the MR height. Further, P2W represents the track (magneticpole) width.

[0018] As an factor for determining the performance of a thin filmmagnetic head, there is an apex angle as represented by θ in FIG. 36Abesides the throat height TH and the MR height MR-H and so on. The apexangle is an angle between a line connecting the corner of a side surfaceof the track surface of the photoresist films 113, 115 and an uppersurface of the top pole layer 116.

[0019] To improve the performance of a thin film magnetic head, it isimportant to form the throat height TH, the MR height MR-H and the apexangle θ as shown in FIG. 36A precisely.

[0020] Especially these days, for enabling high surface density writing,that is to form a recording head with a narrow track structure,submicron measurement of equal to or less than 1.0 μm is required forthe track width P2W. For that, a technique for processing the top poleto submicron using a semiconductor processing technique is required.Further, utilizing magnetic materials which has high saturation magneticflux density for the magnetic pole is desired following theimplementation of the narrow track structure.

[0021] Here, the problem is that it is difficult to precisely form thetop pole layer 116 on a coil area (apex area) being protruded like amountain covered with photoresist films (for example, the photoresistfilms 113,115 shown in FIG. 36A).

[0022] As a method of forming the top pole, frame plating method, shownin, for example, Japanese Patent Application laid-open in Hei 7-262519,is used. When the top pole is formed by the frame plating method, first,a thin electrode film made of, for example, permalloy is formed all overthe apex area. Next, photoresist is applied on it, and by patterning itthrough photolithography, a frame for plating is formed. Further, thetop pole is formed through plating method having the electrode filmformed earlier as a seed layer.

[0023] By the way, the apex area and other areas have, for example,equal to or more than 7 to 10 μm differences in heights. If the filmthickness of the photoresist formed on the apex area is required to beequal to or more than 3 μm, a photoresist film of equal to or more than8 to 10 μm in thickness is formed in the lower part of the apex areasince the photoresist with liquidity gathers into a lower area. To forma narrow track as described, a pattern with submicron width is requiredto be formed with a photoresist film. Accordingly, forming a micropattern with submicron width with a photoresist film of equal to or morethan 8 to 10 μm in thickness is required. However, it has been extremelydifficult.

[0024] Further, during an exposure of photolithography, a light for theexposure reflects by an electrode film made of, for example, permalloy,and the photoresist is exposed also by the reflecting light causingdeformation of the photoresist pattern. As a result, the top pole cannot be formed in a desired shape and so on since side walls of the toppole take a shape of being rounded. As described, with a related art, ithas been extremely difficult to precisely control the track P2W and toprecisely form the top pole so as to implement a narrow track structure.

[0025] For the reasons described above, as shown in a procedure of anexample of a related art in FIGS. 33A and 33B˜36A and 36B, a method ofconnecting the pole tip 110 and a yoke area-cum-top pole layer 116 afterforming a track width of equal to or less than 1.0 μm with the pole tip110 which is effective for forming a narrow track of a recording head,that is, a method of dividing the regular top pole into the pole tip 110for determining the track width and the top pole layer 116 which becomesthe yoke area for inducing magnetic flux is employed (Ref. JapanesePatent Application laid-open Sho 62-245509, Sho 60-10409). By dividingthe top pole into two as described, the pole tip 110 can befine-processed to submicron width on a flat surface of the write gaplayer 109.

[0026] However, there still exists problems as follows regarding thethin film magnetic head.

[0027] (1) First, in the magnetic head of a related art, the throatheight is determined in an edge of a further side from the track surface118 of the pole tip 110. However, if the width of the pole tip 110becomes narrower, a pattern edge is formed being rounded byphotolithography. As a result, the throat height which is required tohave a highly precise measurement becomes inhomogeneous, which leads toa state where the throat height and the track width of magnetoresistiveelement becomes unbalanced in a procedure of processing and polishingthe track surface. For example, when 0.5˜0.6 μm of the track width isneeded, a problem in which an edge of a further side from the tracksurface 118 of the pole tip 110 is shifted from the throat height 0position to the track surface 118 side and writing gap is widely opened,often causing a problem in which writing of recording data can not beperformed.

[0028] (2) Next, as described above, in the magnetic head of a relatedart, it is not required to fine-process the top pole layer 116 asprecise as the pole tip 110, since the track width of the recording headis determined by the pole tip 110 of the divided top pole. However,since the location of the top pole layer 116 is determined in the upperarea of the pole tip 110 by positioning of photolithography, if both arelargely shifted to one side when looking at the structure from the tracksurface 118 (FIG. 36A) side, so-called side write for performing writingon the top pole layer 116 side occurs. As a result, the effective trackwidth becomes wider and a problem that writing is performed in a regionother than the originally designated data recording region in a harddisk occurs.

[0029] Further, when the track width of the recording head becomesextremely finer, especially equal to or less than 0.5 μm, a processprecision of submicron width is required in the top pole layer 116. Thatis, if the measurement difference in a lateral direction of the pole tip110 and the top pole layer 116 is too significant when looking at itfrom the track surface 118 side, as described above, a side write occursand a problem that writing is performed in a region other than theoriginally designated data recording region in a hard disk occurs.

[0030] As a result, not only the pole tip 110 but also the top polelayer 116 is required to be processed to the submicron width, however,it is difficult to perform fine-process of the top pole layer 116 sincethere is a significant difference in heights as described above in theapex area under the top pole layer 116.

[0031] (3) Further, in the magnetic head of a related art, there is aproblem that it is difficult to shorten a yoke length. That is, thenarrower the coil pitch becomes, the easier the achievement of a headwith short yoke length becomes and, especially, a recording head with ahigh frequency characteristics can be formed. However, when the coilpitch is made indefinitely small, the length of outer periphery end ofthe coil becomes a main factor for preventing the yoke length fromshortening for the position of the throat height 0. The yoke length canbe made shorter with two-layered coil than one-layered coil so that mostof the recording heads for high frequency employ the two-layered coil.However, in the magnetic head of a related art, after forming a firstlayer of coil, a photoresist film of about 2 μm is formed in order toform an insulating film between the coils. As a result, a small apexarea having a rounded shape is formed in the outer peripheral end of thefirst layer of the coil. Next, a second layer of the coil is to beformed on it, however, etching to have a seed layer can not be performedin the slope of the apex area causing the coil to short-circuit, whichmakes it impossible to form the second layer of the coil. Accordingly,the second layer of the coil needs to be formed on a flat area. When theslope of the apex is 45˜55°, if the thickness of the coil is 2˜3 μm andthe thickness of the insulating film between the coils is 2 μm, 8˜10 μmwhich is twice of 4 ˜5 μm, (the distance from the contact area of thetop pole and the bottom pole to the outer peripheral end of the coilalso needs to be 4˜5 μm) the distance from the outer peripheral end ofthe coil to the vicinity of the throat height 0 position is needed. Thishas been the main factor for preventing the yoke length from reducing.For example, when forming two layers of coils with 11 turns withline/space being 1.0 μm/ 1.0 μm, suppose the first layer is 6 turns andthe second layer is 5 turns, then, the length of the coil of the yokelength is 11 μm. Here, since 8˜10 μm is required in the apex area of theouter peripheral end, reduction of the yoke length to equal to or lessthan 19˜21 μm is impossible. This has prevented the high frequencycharacteristics from improving.

SUMMARY OF THE INVENTION

[0032] The invention is presented to solve these problems. The firstobject is to provide a thin film magnetic head which can preciselycontrol the throat height in the recording head and a method ofmanufacturing the same.

[0033] Further, the second object is to provide a thin film magnetichead, which can fine-process the submicron width of the top pole layerin addition to the precise control of the throat height, whosecharacteristic of the recording head is improved, and a method ofmanufacturing the same.

[0034] Further, the third object is, in addition to the precise controlof the throat height, to provide a thin film magnetic head which canreduce the yoke length of the recording head and whose high frequencycharacteristic is improved, and a method of method of manufacturing thesame.

[0035] A thin film magnetic head of the invention has at least twomagnetic layers which includes a first magnetic pole and a secondmagnetic pole being magnetically connected to each other, part of sidesof which facing a recording medium face each other through a write gaplayer, and one or more than two layers of thin film coil for generatingmagnetic flux. The thin film magnetic head comprises a first magneticlayer, a first pole formed being divided from the first magnetic layer,while the opposite surface of a neighboring surface of the write gaplayer being magnetically coupled to part of region of the first magneticlayer, a second magnetic layer including the second magnetic pole, andan insulating layer formed with inorganic materials, and formedextendedly at least from a surface of the first magnetic pole which isopposite of a side facing the recording medium to one of the surfaces ofthe first magnetic layer.

[0036] In the thin film magnetic head of the invention, as the firstpole is formed to be divided from the first magnetic layer and to haveconvex shape against the first magnetic layer, the insulating layer madeof an inorganic material is formed adjacent to the first magnetic pole.Accordingly, a phenomenon (protrusion) in which a track pole (top poleor pole tip) sticks out to ABS by thermal expansion generated duringoperation on the hard disk can be suppressed to minimum. Further, thethroat height of the recording head portion is precisely determined bymaking the length of the first magnetic pole from the surface facing therecording medium towards inner direction equal to the length of thethroat height of the recording head. Further, by burying the thin filmcoil in a region in which the insulating layer is formed, the step ofthe apex area including the coil becomes lower comparing to that of arelated art. As a result, when forming the second magnetic pole byphotolithography technique, difference in the thickness of photoresistfilm on the top and the bottom of the apex area is decreased.Accordingly, micronizing the submicron measurement of the secondmagnetic pole can be achieved.

[0037] A thin film magnetic head of the invention can be furtherachieved with the embodiments in the followings in addition to thestructures described above.

[0038] That is, in the thin film magnetic head of the invention, thelength from a surface of the first magnetic pole facing the recordingmedium is preferable to be equal to the length of the throat height ofthe recording head. Further, a structure in which at least part of afilm-thickness direction of, at least, a layer of the thin film coil isformed to be placed in a region where the insulating layer is formed ispreferable.

[0039] Further, in the thin film magnetic head of the invention, theinsulating layer may include a first insulating layer being extendedlyformed from a surface of the first magnetic pole which is opposite of aside facing the recording medium to one of a surface of the magneticlayer, and a second insulating layer being formed at least betweenwindings of the thin film coil. Further, a surface of the insulatinglayer which is opposite of a neighboring surface of the first magneticlayer may be formed to be the same surface substantially as a surface ofthe first magnetic pole which is opposite of a neighboring surface ofthe write gap layer.

[0040] Further, in the thin film magnetic head of the invention, thesecond magnetic pole may be formed being divided from the secondmagnetic layer, and may be magnetically coupled to the second magneticlayer in, at least, part of a surface of an opposite side of aneighboring surface of the write gap layer.

[0041] Further, in the thin film magnetic head of the invention, widthof the first magnetic pole along a surface facing the recording mediummay be formed to be wider than width of the second magnetic pole.

[0042] Further, in the thin film magnetic head of the invention, thesecond magnetic pole may be formed in the same length as the firstmagnetic pole from the surface facing the recording medium to the innerside.

[0043] Further, the length of the second magnetic pole may be formedlonger than that of the first magnetic pole. With such a structure, thecontact area of the second magnetic pole and the second magnetic layercan be sufficiently maintained and magnetic coupling of the secondmagnetic pole and the second magnetic layer be better performed.

[0044] Further, the thin film magnetic head of the invention maycomprise a first connecting portion formed adjacent to the firstmagnetic layer in the vicinity of an edge of the second magnetic layerwhich is an opposite side of a side facing the recording medium, and asecond connecting portion formed adjacent to the second magnetic layerin a place facing the first connecting portion. Further, the areas ofthe first connecting portion and the second connecting portion facingeach other may be different. Preferably, the area of the secondconnecting portion is formed larger than that of the first connectingportion.

[0045] Further, in the thin film magnetic head of the invention, thesecond magnetic layer is preferably formed in a place which is recessedfrom a surface facing the recording medium.

[0046] Further, in the thin film magnetic head of the invention, thefirst insulating layer may be formed along surfaces of both sides of thefirst magnetic pole except for an edge surface of a side facing therecording medium.

[0047] Further, in the thin film magnetic head of the invention, thewhole part of film-thickness direction of the thin film coil may beformed in a region where the first insulating layer is formed. Further,a surface of the thin film coil which is opposite of a neighboringsurface of the first insulating layer may be formed to be substantiallythe same surface as a neighboring surface of the first magnetic polewith the write gap layer.

[0048] Further, in the thin film magnetic head of the invention, thesecond insulating layer may be formed to be substantially the samesurface as a neighboring surface of the first magnetic pole with thewrite gap layer.

[0049] Further, in the thin film magnetic head of the invention, asurface of the second magnetic layer, which is on the opposite side ofthe facing surface of the write gap layer, may be flat. Further, thethin film coil may be buried in the insulating layer and, the surface ofthe second magnetic layer, which is in the opposite side of the facingsurface of the write gap layer may be made flat.

[0050] Further, in the thin film magnetic head of the invention, one ofthe surfaces of the write gap layer may be formed to cover the secondinsulating layer and the thin film coil. Further, a third magnetic layermay be, at least, formed extendedly from a surface of the secondmagnetic pole which is opposite of a side facing the recording medium toother surface of the write gap layer. Further, the thin film magnetichead may have a structure, which comprises at least one layer of thinfilm coil formed being covered with other insulating layer which isdifferent from the first to the third insulating layers, between thethird insulating layer and the second magnetic layer. Further, the thirdinsulating layer and other insulating layer may be formed to besubstantially the same surface with a surface of the second magneticpole which is opposite of a neighboring surface of the write gap layer.

[0051] Further, in the thin film magnetic head of the invention, thewidth of the second magnetic pole which is on the opposite-surface sideof a side facing the recording medium may be formed to be wider than thewidth of a side facing the recording medium. A surface of the firstmagnetic pole which is opposite of a side facing the recording mediummay be formed to incline towards the first magnetic layer.

[0052] Further, the thin film magnetic head of the invention may beformed to comprise a magnetoresistive element for reading out.

[0053] A method of manufacturing a thin film magnetic head of theinvention includes: a step of forming a first magnetic pole on the firstmagnetic layer so as to be magnetically coupled to part of a region ofthe first magnetic layer after forming the first magnetic layer; a stepof forming an insulating layer with inorganic materials extendedly, atleast, from a surface of the first magnetic pole which is the oppositeof a side facing the recording medium to one of the surfaces of thefirst magnetic layer; and a step of forming a second magnetic layerincluding the second magnetic pole, at least, after forming a write gaplayer on the first magnetic pole.

[0054] In a method of manufacturing a thin film magnetic head of theinvention, the first magnetic pole is formed having a convex shapeagainst the first magnetic layer, and an insulating layer made of aninorganic material is formed adjacent to the first magnetic pole. As aresult, the throat height can be determined precisely by making thelength of the first pole from the facing surface of the recording mediumto the inner direction equal to the length of the throat height of therecording head.

[0055] A method of manufacturing a thin film magnetic head of theinvention can be further achieved with the embodiments in the followingsin addition to the structures described above.

[0056] That is, a method of manufacturing a thin film magnetic head ofthe invention may include a step in which at least part of afilm-thickness direction of, at least, a layer of the thin film coil isformed to be placed in a region where the insulating layer is formed.

[0057] Further, a method of manufacturing a thin film magnetic head ofthe invention may include a step of forming insulating layers extendedlyfrom a surface of the first magnetic pole which is opposite of a sidefacing the recording medium to one of the surfaces of the first magneticlayer, and a step of forming a second insulating layer, at least,between windings of the thin film coil.

[0058] Further, a method of manufacturing a thin film magnetic head ofthe invention may include a step of flattening a surface of the secondinsulating layer which is the opposite of a neighboring surface of thefirst magnetic layer so as to make it substantially the same surface asa surface of the first magnetic pole which is the opposite of aneighboring surface of the write gap layer.

[0059] Further, a method of manufacturing a thin film magnetic head ofthe invention may include a step of forming the second magnetic layer soas to be magnetically coupled to, at least, part of the first magneticpole after forming the second magnetic pole on the write gap layer.

[0060] Moreover, the length of the second magnetic pole may be longerthan that of the first magnetic pole. Further, in the vicinity of theedge of the second magnetic layer, which is in the opposite side of thefacing side of the recording medium, the thin film magnetic head maycomprise the first connecting portion formed adjacent to the firstmagnetic layer, and the second magnetic layer formed adjacent to thesecond magnetic layer in a position facing the first connecting portion.Further, the area of sides facing each other of the respective firstconnecting portion and the second connecting portion may be formeddifferent.

[0061] Further, in a method of manufacturing a thin film magnetic headof the invention, the width of the first magnetic pole along a surfacewhich is facing the recording medium may be formed to be wider than thatof the second magnetic pole.

[0062] Further, in a method of manufacturing a thin film magnetic headof the invention, the whole part of a film-thickness direction of thethin film coil may be formed in a region where the first insulatinglayer is formed.

[0063] Further, in a method of manufacturing a thin film magnetic headof the invention, after flattening the second insulating layer, a writegap layer may be formed on the second insulating layer; after formingthe second magnetic pole on the write gap layer, a third insulatinglayer may be formed at least on the write gap layer; then, at least onelayer of thin film coil may be formed on the third insulating layer onthe write gap layer; and the thin film coil is covered with otherinsulating layer which is different from the first to third insulatinglayers.

[0064] Further, in a method of manufacturing a thin film magnetic headof the invention, after forming the other insulating layer withinorganic materials, the other insulating layer may be flattened so thatits surface forms the same surface with the surface of the secondmagnetic pole and, then, the second magnetic layer may be formed on thesecond magnetic pole and the other insulating layer being flattened orafter selectively forming the other insulating layer with organicmaterials, the second magnetic layer may be formed on the secondmagnetic pole and the other insulating layer.

[0065] Further, in a method of manufacturing a thin film magnetic headof the invention, a surface of the second magnetic layer which is anopposite-side of a facing surface of the write gap layer may be formedto be flat. Further, the thin film coil may be buried in a region wherethe insulating layers are formed, and a surface of the second magneticlayer, which is in an opposite-side of a facing surface of the write gaplayer may be flattened.

[0066] Further, a method of manufacturing a thin film head of theinvention may include a step of forming a magneto resistive element forreading out.

[0067] Other objects, characteristics and effects of the invention willbe made evident in the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0068]FIGS. 1A and 1B are cross sections for describing a manufacturingprocedure of a thin film magnetic head according to a first embodimentof the invention.

[0069]FIGS. 2A and 2B are cross sections for describing the procedurefollowing FIG. 1.

[0070]FIGS. 3A and 3B are cross sections for describing the procedurefollowing FIG. 2.

[0071]FIGS. 4A and 4B are cross sections for describing the procedurefollowing FIG. 3.

[0072]FIGS. 5A and 5B are cross sections for describing the procedurefollowing FIG.4.

[0073]FIGS. 6A and 6B are cross sections for describing the procedurefollowing FIG. 5.

[0074]FIGS. 7A and 7B are cross sections for describing the procedurefollowing FIG. 6.

[0075]FIGS. 8A and 8B are cross sections for describing the procedurefollowing FIG. 7.

[0076]FIG. 9 is a plan view of a thin film magnetic head manufacturedthrough the first embodiment of the invention.

[0077]FIGS. 10A and 10B are cross sections for describing theconstitution of a thin film magnetic head according to the firstembodiment of the invention.

[0078]FIG. 11 is a plan view of a thin film magnetic head manufacturedthrough a second embodiment of the invention.

[0079]FIGS. 12A and 12B are cross sections for describing theconstitution of a thin film magnetic head according to a thirdembodiment of the invention.

[0080]FIGS. 13A and 13B are cross sections for describing theconstitution of a thin film magnetic head according to a fourthembodiment of the invention.

[0081]FIGS. 14A and 14B are cross sections for describing theconstitution of a thin film magnetic head according to a fifthembodiment of the invention.

[0082]FIGS. 15A and 15B are cross sections for describing theconstitution of a thin film magnetic head according to a fifthembodiment of the invention.

[0083]FIGS. 16A and 16B are cross sections for describing theconstitution of a thin film magnetic head according to a sixthembodiment of the invention.

[0084]FIGS. 17A and 17B are cross sections for describing theconstitution of a thin film magnetic head according to a seventhembodiment of the invention.

[0085]FIGS. 18A and 18B are cross sections for describing theconstitution of a thin film magnetic head according to a eighthembodiment of the invention.

[0086]FIGS. 19A and 19B are cross sections for describing themanufacturing procedure of a thin film magnetic head according to aninth embodiment of the invention.

[0087]FIGS. 20A and 10B are cross sections for describing the procedurefollowing FIG. 19.

[0088]FIGS. 21A and 21B are cross sections for describing the procedurefollowing FIG. 20.

[0089]FIGS. 22A and 22B are cross sections for describing the procedurefollowing FIG. 21.

[0090]FIGS. 23A and 23B are cross sections for describing the procedurefollowing FIG. 22.

[0091]FIGS. 24A and 24B are cross sections for describing the procedurefollowing FIG. 23.

[0092]FIGS. 25A and 25B are cross sections for describing the procedurefollowing FIG. 24.

[0093]FIG. 26 is a plan view of a thin film magnetic head manufacturedthrough the ninth embodiment of the invention.

[0094]FIG. 27 is a cross section for describing the constitution of athin film magnetic head according to a tenth embodiment of theinvention.

[0095]FIG. 28 is a cross section for describing the constitution of athin film magnetic head according to a eleventh embodiment of theinvention.

[0096]FIG. 29 is a cross section for describing a modification exampleof a thin film magnetic head according to the first embodiment of theinvention.

[0097]FIG. 30 is also a cross section for describing a modificationexample of a thin film magnetic head according to the first embodimentof the invention.

[0098]FIGS. 31A and 31B are cross sections for describing amanufacturing procedure of a thin film magnetic head according to theinvention.

[0099]FIGS. 32A and 32B are cross sections for describing the procedurefollowing FIG. 31.

[0100]FIGS. 33A and 33B are cross sections for describing the procedurefollowing FIG. 32.

[0101]FIGS. 34A and 34B are cross sections for describing the procedurefollowing FIG. 33.

[0102]FIGS. 35A and 35B are cross sections for describing the procedurefollowing FIG. 34.

[0103]FIGS. 36A and 36B are cross sections for describing the procedurefollowing FIG. 35.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0104] Embodiments of the invention will be described with reference tothe drawings in the followings.

First Embodiment

[0105]FIGS. 1A and 1B to FIGS. 8A and 8B illustrate a manufacturingprocedure of a composite thin film magnetic head as a thin film magnetichead according to the first embodiment of the invention respectively.FIGS. 1A˜8A show cross sections vertical to the track surface (ABS), andFIGS. 1B˜8B show cross sections parallel to the track surface of themagnetic pole portion.

[0106] First, the constitution of a composite thin film magnetic headaccording to the embodiment of the invention will be described withreference to FIGS. 8A and 8B. The magnetic head comprises amagnetoresistive reading head (called reproduction head portion in thefollowings) 1A for reproduction and a inductive recording head (calledrecording head portion in the followings) 1B for recording.

[0107] The reproduction head portion 1A is a pattern of magnetoresistivefilm (called GMR film in the followings) 15 being formed on a substrate11 made of, for example, aluminum oxide and titanium carbide (AL₂O₃ TiC)through an insulating layer 12 formed with, for example, alumina(aluminum oxide, A₂O₃), a bottom shield layer 13 formed with, forexample, permalloy (NiFe), and a shield gap layer 14 formed with, forexample, alumina in order. Further, a lead terminal layer 15 a made ofmaterial such as tantalum (Ta) or tungsten (W) which does not diffuseonto the GMR films is formed on the shield gap layer 14, and the leadterminal layer 15 a is electrically connected to a GMR film 15. The GMRfilm 15 is formed with a free layer made of, for example, permalloy(NiFe alloy) or with several types of materials having magnetoresistive,such as anti-ferromagnetic film made of PtMn, IrMn, and RuRhMn. A shieldgap layer 17 made of such as alumina is stacked on the GMR film 15 andthe lead terminal layer 15 a. In other words, the GMR film 15 and thelead terminal layer 15 a are buried between the shield gap layers 14 and17. Further, it is not specifically limited to the GMR film 15 but alsoother magnetoresistive film such as the AMR film can be used in theinvention.

[0108] The recording head portion 1B is a top pole formed on thereproduction head portion 1A through the upper shield layer-cum-bottompole for the GMR film 15 and a write gap layer 22.

[0109] In the embodiment, the bottom pole is formed being divided into abottom pole layer (bottom pole) 18 formed on the shield gap layer 17,and a bottom pole tip 19 a formed on the bottom pole layer 18 on thetrack surface side. Likewise, the top pole is divided into two:one isthe top pole tip 23 a formed on a write gap layer 22 on the bottom poletip 19 a on the track surface side, and the other is a yoke-cum-top polelayer (top pole ) 25 which has a contact with the top pole tip 23 a, andis formed along the upper surface of the apex including the coil whichis to be described later. The top pole layer 25 is magnetically coupledto the bottom pole layer 18 through the top connecting portion 23 b andthe bottom connecting portion 19 b in the position which is the opposite(right-hand side in FIG. 8A) of the track surface.

[0110] The bottom pole layer 18, the bottom pole tip 19 a, the bottomconnecting portion 19 b, the top pole tip 23 a, the top connectingportion 23 b and the top pole layer 25 are formed with, for example,high saturation flux density material (Hi—Bs material), for example,NiFe (Ni: 50 weight percentage, Fe: 50 weight percentage), NiFe (Ni: 80weight percentage, Fe: 20 weight percentage), FeN, FeZrNP, CoFeN and soon respectively.

[0111] In the recording head portion 1B, the bottom pole tip 19 b facingthe top pole tip 23 a has a trim structure in which part of the surfacearea is processed to a convex shape. As a result, when writing data,widening of the effective write track width, that is, widening of themagnetic flux in the bottom pole can be suppressed.

[0112] In the embodiment, the bottom pole layer 18 corresponds to thefirst magnetic layer of the invention, and the bottom pole tip 19 a tothe first magnetic pole of the invention respectively. Further, the toppole tip 23 a corresponds to the second magnetic pole of the invention,and the top pole layer 25 to the second magnetic layer of the inventionrespectively.

[0113] In the embodiment, a first layer of the thin film coil 21 isformed in a concave region between bottom pole tip 19 a and the bottomconnecting portion 19 b on the bottom pole layer 18. That is, aninsulating layer 20 a is formed in inner wall surface (bottom andside-wall surface) of the concave region, and a thin film coil 21 isformed on the insulating layer 20 a. Between the bundles of coils of thethin film coil 21 is buried with an insulating layer 20 b, and thesurface of the insulating layer 20 b and the bottom pole tip 19 a areflattened so that both surface make the same surface. For this, a stepof the apex area including a thin film coil 24 which is to be describedlater is lowered about the size of the thin film coil 21. The insulatinglayer 20 a corresponds to the first insulating layer of the invention,and the insulating layer 20 b to the second insulating layer of theinvention respectively.

[0114] A write gap layer 22 is extended on the flattened insulatinglayer 20 b and the thin film coil 21. An insulating layer 20 c is formedin the concave region between the top pole tip 23 a and the topconnecting portion 23 b on the write gap layer 22. A second layer of thethin film coil 24 is formed on the insulating layer 20 c. The thin filmcoil 24 is covered with an insulating layer 20 d made of, for example,alumina. The insulating layer 20 c corresponds to a third insulatinglayer of the invention and the insulating layer 20 d corresponds toother insulating layer of the invention respectively.

[0115] A yoke-cum-top pole layer 25 is formed on the insulating layer 20d. The top pole layer 25 is covered with an over coat layer 26. The thinfilm coils 21 and 24 are electrically connected to each other on theborder surface between the insulating layer 20 b and the insulatinglayer 20 d, though not shown in the figure.

[0116] With the magnetic head, information is read out from a magneticdisk, not shown in the figure, by using megnetoresistive effect of theGMR film 15 in the reproduction head portion 1A, while information iswritten to a magnetic disk by using a change of magnetic flux betweenthe top pole tip 23 a and the bottom pole tip 19 a by the thin filmcoils 21 and 24 in the recording head portion 1B.

[0117] Next, a manufacturing method of the composite thin film magnetichead is to be described.

[0118] In the manufacturing method according to the embodiment of theinvention, first, as shown in FIG. 1, an insulating layer 12 of about3˜5 μm in thickness, made of, for example, alumina (Al₂O₃) is formed ona substrate 11 made of, for example, aluminum oxide and titanium carbide(Al₂O₃.TiC) by, for example, sputtering method. Next, a bottom shieldlayer 13 for a reproduction head is formed by selectively formingpermalloy (NiFe) of about 3 μm in thickness on the insulating layer 12by plating method using a photoresist film as a mask. Then, an aluminafilm (not shown in the figure) of about 4˜6 μm is formed by, forexample, sputtering or CVD (Chemical Vapor Deposition) method and isflattened by CMP.

[0119] Next, as shown in FIG. 2, a shield gap layer 14 is formed bydepositing, for example, alumina of about 100˜200 nm in thickness on thebottom shield layer 13 by sputtering method. Then, an MR film 15 forforming such as an MR element for reproduction is formed in tens ofnanometers in thickness on the shield gap layer 14, and a desired shapeis obtained by photolithography with high precision. Next, a leadterminal layer 15 a facing the GMR film 15 is formed by lift-off method.Next, a shield gap layer 17 is formed on the shield gap layer 14 and thelead terminal layer 15 a , and the GMR film 15 and the lead terminallayer 15 a are buried in the shield gap layers 14 and 17.

[0120] Next, a top shield-cum-bottom pole layer (bottom pole) 18 ofabout 1.0 ˜1.5 μm in thickness, made of, for example, permalloy (NiFe)is formed on the shield gap film 17.

[0121] Next, as shown in FIG. 3, the bottom pole tip 19 a and the bottomconnecting portion 19 b of about 2.0˜2.5 μm in thickness are formed onthe bottom pole layer 18. Here, the bottom pole tip 19 a is formed withthe track side tip portion being in the vicinity of the GMR (MR) height0 position, and with the opposite side of the track surface being in thethroat height 0 position. The bottom pole tip 19 a and the bottomconnecting portion 19 b may be formed with plating films such as NiFe asdescribed, and may also be formed with sputter films such as FeN, FeZrNPand CoFeN.

[0122] Further, the insulating layer 20 a of about 0.3˜0.6 μm inthickness, made of insulating materials such as alumina is formed allover the surface by, for example, sputtering method or CVD method.

[0123] Next, as shown in FIG. 4, a first layer of the thin film coil 21for a inductive-type recording head, made of, for example, copper (Cu)is formed in thickness of about 1.5˜2.5 μm in the concave region formedbetween the bottom pole tip 19 a and the bottom connecting portion 19 bby, for example, electroplating method.

[0124] Next, as shown in FIG. 5, after forming the insulating layer 20 bof about 3.0˜4.0 μM in thickness, made of an insulating material such asalumina all over the surface by sputtering method, the surface isflattened by, for example, CMP method so as to make the surface of thebottom pole tip 19 a be exposed. Here, in the embodiment, the surface ofthe thin film coil 21 is exposed at the same time, however, part of thesurface, except for the connecting portion of the thin film coil 21 anda second layer of the thin film coil 24 which is to be described lateris not required to be exposed.

[0125] Next, as shown in FIG. 6, a write gap layer 22 of about 0.2˜0.3μm in thickness, made of an insulating material such as alumina isformed by sputtering method. The write gap layer 22 may be formed withaluminum nitride (AlN), silicon oxide, silicon nitride and so on,besides with alumina. Then, an opening 22 a for connecting the top poleand the bottom pole is formed by patterning the write gap layer 22 byphotolithography.

[0126] Further, the top pole tip 23 a for determining the track width ofthe recording head is formed on the write gap layer 22 byphotolithography. That is, a magnetic layer of about 2.5˜3.5 μm inthickness, made of high saturation flux density material (Hi—Bsmaterial), for example, NiFe (Ni: 50 weight percentage, Fe: 50 weightpercentage), NiFe (Ni: 80 weight percentage, Fe: 20 weight percentage),FeN, FeZrNP, CoFeN and so on is formed on the write gap layer 22 by, forexample, sputtering method. Further, the top pole tip 23 a is formed byselectively removing the magnetic layer by, for example, ion-millingwith Ar (argon) using a photoresist mask, while the top connectingportion 23 b for magnetically connecting the top pole and the bottompole is formed. The top pole tip 23 a and the top connecting portion 23b may be etched using a mask made of inorganic insulating layer such asalumina, instead of using the photoresist mask. Further, it may beformed by, other than the photolithography, plating method or sputteringmethod.

[0127] Further, having the top pole tip 23 a as a mask, the write gaplayer 22 and the bottom pole tip 19 a in the vicinity are etched in aself-aligned manner. That is, a recording track with a trim structure isformed by further etching the bottom pole tip 19 a about 0.3˜0.6 μm byion-milling with Ar after selectively removing the write gap layer 22 byRIE (Reactive Ion Etching) with chlorine gas (Cl₂, CF₄, BCl₂, SF₆ and soon), having the top pole tip 23 a as a mask.

[0128] Further, the insulating layer 20 c of about 0.3˜0.6 μm inthickness, made of, for example, alumina is formed all over the surfaceby, for example, sputtering method or CVD method. Further, a secondlayer of the thin film coil 24 for an inductive-type recording head,made of, for example, copper (Cu) is formed on the insulating layer 20 cin thickness of about 1.5˜2.5 μm by, for example, electroplating.

[0129] Next, as shown in FIG. 7, the insulating layer 20 d of about 3˜4μm in thickness, made of such as alumina is formed all over the surfaceby, for example, sputtering method or CVD method. The insulating layer20 d and the insulating layer 20 c may be formed with other insulatingmaterials such as silicon dioxide (SiO₂) or silicon nitride (SiN)besides with alumina. Then, the insulating layer 20 d and the insulatinglayer 20 c are etched so as to make the surfaces of the top pole tip 23a and the top connecting portion 23 b be exposed, and are flattened sothat the surfaces of the insulating layers 20 c and 20 d, and eachsurface of the top pole tip 23 a and the top connecting portion 23 bforms the same surface.

[0130] Next, as shown in FIG. 8, the top pole layer 25 of about 3˜4 m inthickness is formed using the same material as, for example, the toppole tip 23 a by, for example, electroplating method or sputteringmethod. The top pole layer 25 has a contact with the bottom connectingportion 19 b through the top connecting portion 23 a in a position rearof the thin film coils 21 and 24 from the track surface side (right-handside in FIG. 8A), and is magnetically coupled to the bottom pole layer18. At last, an over coat layer 26 of about 30 μm in thickness, made ofalumina is formed on the top pole layer 25 by, for example, sputteringmethod. A thin film magnetic head is completed by performing a slidermachine processing and by forming a track surface (ABS) of a recordinghead and a reproducing head.

[0131]FIG. 9 is a plan view of a thin film magnetic head according tothe embodiment of the invention. The figure shows a state before theslider machine processing is performed. In these figures, TH representsthe throat height, and the throat height is determined by the top poleside of the edge frame of the insulating layer 20 a, that is, by theopposite side edge frame of the track surface of the bottom pole tip 19a. Further, 21 a represents a lead wire of the thin film coil 21.

[0132] With the embodiment described above, effects described in thefollowings can be obtained.

[0133] (1) In the embodiment, the bottom pole is divided into the bottompole tip 19 a and the bottom pole layer 18, and the bottom pole tip 19 ais formed on a flat surface of the bottom pole layer 18. As a result,the insulating layers 20 a and 20 b made of inorganic materials can beburied in the concave region between the bottom pole tip 19 a and thebottom connecting portion 19 b. Accordingly, the throat height isdetermined by the edge frame of the bottom pole tip 19 a side of theinsulating layer 20 a (that is, edge frame of the opposite side of thetrack surface of the bottom pole tip 19 a). As a result, precise controlof the throat height can be achieved since a pattern shift of the edgeframe by heat annealing or profile deterioration does not occur, unlikethe photoresist film of a related art. Further, precise control of theGMR height and apex angle can be achieved.

[0134] (2) Further, in the embodiment, as shown in FIG. 11, when eachpattern is seen from right above, the width of the bottom pole tip 19 ais made wider than the width of the top pole tip 23 a. As a result, evenif the top pole tip 23 a is a narrow track with half-micron width, themagnetic flux does not saturate in the vicinity of the bottom pole tip19 a.

[0135] (3) Further, in the embodiment, the insulating films 20 a and 20b made of inorganic materials are provided between the thin film coil 21and the top shield-cum-bottom pole layer 18, and the write gap film 22and the insulating layer 20 c are provided between the thin film coils21 and 24. As a result, by adjusting the thickness of each insulatinglayer, a large insulating pressure resistant between each of the thinfilm coils 21 and 24, and the top shield can be obtained so thatinsulating character can be maintained and leaking of the magnetic fluxfrom the thin film coils 21 and 24 can be decreased.

[0136] (4) Further, in the embodiment, the top pole is divided into thetop pole tip 23 a and the top pole layer 25, and the top pole tip 23 ais formed on a flat surface of the bottom pole tip 19 a. As a result,the top pole tip 23 a for determining the recording track width can beformed to a submicron measurement with high precision. In addition, inthe embodiment, a first layer of the thin film coil 21 is buried in theconcave region adjacent to the bottom pole tip 19 a by the insulatinglayer 20 b, while the surface of the insulating layer 20 b is flattenedso that its surface forms the same surface with the surface of thebottom pole tip 19 a. That is, the step of the apex area including asecond layer of the thin film coil 24 becomes lower about the size ofthe first layer of the thin film coil 21 comparing to the structure of arelated art. Accordingly, when forming the top pole layer 25 which has acontact partially with the top pole tip 23 a by photolithography,differences in thickness of the photoresist film in the top and thebottom of the apex area is decreased. As a result, micronization of thesubmicron measurement of the top pole layer 25 can be achieved.Accordingly, with the thin film magnetic head obtained through theembodiment, high surface density recording by a recording head can beachieved, and performance of the recording head can be improved bystacking the coils to two layers and three layers. When applyingphotolithography to the top pole tip 23 a and the top pole layer 25, byusing an inorganic insulating layer as a mask instead of thephotoresist, micronization of the top pole tip 23 a and the top polelayer 25 with higher precision can be achieved. Further, even in a casewhere the top pole tip 23 a and the top pole layer 25 are formed by suchas sputtering, other than photolithography, micronization of the toppole tip 23 a and the top pole layer 25 can be achieved since influenceof the steps of the apex area is decreased as well.

[0137] Further, in the embodiment, since there is no slope area of thephotoresist pattern, unlike that of a related art, the first and thesecond layer of the thin film coils 21 and 24 can be formed on a flatarea so that the distance between the coil outer peripheral edge by theslope and the throat height 0 position does not prevent the yoke lengthfrom shortening. Accordingly, in the embodiment, the yoke length can bemade shorter, and high frequency characteristic of the recording headcan be improved prominently. In the embodiment, it can be designed witha locating error by photolithography of equal to, or less than 0.1μm˜0.2 μm, so that the yoke length can be decreased to equal to or lessthan 50% of that of a related art.

[0138] (6) Further, in the embodiment, the magnetic layers such as thetop pole tip 23 a and the top pole layer 25 are formed with highsaturation flux density (Hi—Bs) materials, so that, even if the trackwidth becomes narrower, the magnetic flux generated in the thin filmcoils 21 and 24 does not saturate on the way, but effectively reach thetop pole tip 23 a and the bottom pole tip 19 a. As a result, a recordinghead without a magnetic loss can be achieved.

[0139] (7) Further, in the embodiment, the top pole layer 25 formed onthe top pole tip 23 a for determining the track width is not exposed tothe track surface, so that side write by the top pole layer 25 does notoccur.

[0140] Other embodiment of the invention will be described in thefollowings. In the description, like numerals are adopted to thestructures identical to the first embodiment and the description isomitted. The distinguished structures will be described in thefollowings.

Second Embodiment

[0141]FIGS. 10A and 10B show the constitution of a composite thin filmmagnetic head according to a second embodiment of the invention. In thefirst embodiment, the top pole layer 25 is formed in a position recessedfrom the track surface, however, in this embodiment, the top pole layer25′ along with the top pole tip 19 a are exposed to the track surface.Here, by having the thickness of the top pole tip 23 a, for example, 2˜3μm, side write can be avoided without having a structure in which thetop pole layer is recessed from the track surface (recessed structure).Other operation effects are identical to the first embodiment. FIG. 11shows a plan view of a thin film magnetic head according to theembodiment.

[0142] In the embodiment, as shown in FIGS. 12A and 12B, the procedureuntil forming the second layer of the thin film coil 24 is identical tothe first embodiment. After that, the thin film coil 24 is covered witha photoresist film 30, then, the top pole layer 25 is formed on thephotoresist film 30 without the pole tip being exposed to the tracksurface. In the embodiment, unlike the first embodiment, flattening thesurface by CMP after forming the second layer of the thin film coil 24is not performed. Accordingly, manufacturing cost is decreased comparingto the first embodiment. The second layer of the thin film coil 24 withfive turns is formed in a flat area of the first layer of the thin filmcoil 21 with six turns, so that the distance from the outer peripheralend of the thin film coil 24 to the throat height 0 position does notaffect the yoke length. Other operation effects are identical to thoseof the first embodiment.

Fourth Embodiment

[0143]FIGS. 13A and 13B show a fourth embodiment of the invention. Inthe embodiment, the structure of the top pole is not divided into two.In other words, a second layer of the thin film coil 24 is formed on thewrite gap layer 22 without forming the top pole tip, then, the thin filmcoil 24 is covered with the photoresist film 30. Then, the top polelayer 25′ is formed on the photoresist film 30 with the pole tip (poleportion) being exposed to the track surface. In the embodiment, unlikethe first embodiment, flattening the surface by CMP after forming thesecond layer of the thin film coil 24 is not performed, so that themanufacturing cost is decreased comparing to the first embodiment. Otheroperation effects are identical to those of the first embodiment.

Fifth Embodiment

[0144]FIGS. 14A and 14B show a composite thin film magnetic headaccording to a fifth embodiment of the invention. In the magnetic head,the coil portion is the thin film coil 21 with a single layeredstructure, and the thin film coil 21 is formed with narrower pitch thanthe embodiments described above. Further, an insulating layer 20 e of,for example, 1.0 μm in thickness, made of photoresist is formed on thethin film coil 21and the write gap layer 22 is formed, then, the toppole layer 25″ is formed to be exposed to the track surface withoutforming the top pole tip. In the embodiment, the top pole layer 25″ canbe formed directly on the flattened surface so that micronization of thetrack width of the recording head can be achieved further than theembodiments described above.

[0145] As shown in FIGS. 15A and 15B, without forming the insulatinglayer 20 e (FIG. 14A), the same effect as described above can beobtained also in a case where the write gap layer 22 is formed on thebottom pole tip 19 a and the thin film coil 21, and the top pole layer25″ is formed, then, the surface of the top pole layer 25″ is flattenedby, for example, CMP method.

Sixth Embodiment

[0146]FIGS. 16A and 16B show a sixth embodiment of the invention. Theembodiment has a structure in which the whole part of a first layer ofcoil forming portion is buried by the insulating layer 20 b made of, forexample, alumina in the first embodiment (FIG. 8). The description willbe omitted since the effects of the embodiment are substantiallyidentical to those of the first embodiment.

Seventh Embodiment

[0147]FIGS. 17A and 17B show a seventh embodiment of the invention. Theembodiment has a structure in which the whole part of the first layer ofcoil forming portion is buried by the insulating layer 20 b made of, forexample, alumina in the second embodiment (FIG. 10). The description isto be omitted since the effects of the embodiment are substantiallyidentical to those of the second embodiment.

Eighth Embodiment

[0148]FIGS. 18A and 18B show an eighth embodiment of the invention. Theembodiment has a structure in which the whole part of the first layer ofcoil forming portion is buried by the insulating layer 20 b made of, forexample, alumina in the third embodiment (FIG. 12), and the two layersof the thin film coils 24 and 24 a are covered with the photoresist film30. The description is to be omitted since the effects of the embodimentare substantially identical to those of the third embodiment.

[0149]FIGS. 19A and 19B to FIGS. 25A and 25B show the manufacturingprocedure of a thin film magnetic head according to a ninth embodimentof the invention.

[0150] In the embodiment, as shown in FIGS. 25A and 25B, the top poletip 23 a is formed longer than the bottom pole tip 19 a. Further, thewidth of the top connecting portion 23 b is different from the width ofthe bottom connecting portion 19 b, that is, the areas of the two aredifferent. Specifically, the area of the top connecting portion 23 b islarger than the area of the bottom connecting portion 19 b. Further, thebottom connecting portion 19 b has a contact with the center position ofthe top connecting portion 23 b. As a result, flow of the magnetic fluxfrom the top pole layer 25 to the bottom pole layer 18 becomes smooth.

[0151] The manufacturing method of the thin film magnetic head issubstantially identical to the first embodiment except that the top poletip 23 a is formed longer than the bottom pole tip 19 a from the tracksurface to inside, the top connecting portion 23 b is formed wider thanthe bottom connecting portion 19 b, and the bottom connecting portion 19b has a contact with the center position of the top connecting portion23 b. Accordingly, description in detail is to be omitted.

[0152]FIG. 26 is a plan view of a thin film magnetic head according tothe embodiment. This figure shows a state before the slider machineprocessing is performed. In the figure, TH represents the throat height,and the throat height TH is determined by the pole tip side edge frameof the insulating layer 20 a, that is, the opposite side frame edge ofthe track surface of the bottom pole tip 19 a. In the figure, TH is GMRheight since the throat height TH is met with the GMR height. One of theedge of the lead terminal 21 a is connected to the thin film coil 21.The other edge of the lead terminal 21 a is connected to an electrodeextract pad (not shown in the figure). Further, the other edge of thelead terminal layer 15 a whose other edge is connected to the MR element15 is also connected to the electrode extract pad (not shown in thefigure).

[0153] In the embodiment, in addition to the effects of the firstembodiment, the effects which will be described in the followings can befurther obtained.

[0154] (1) In the embodiment, since the top pole tip 23 a is formed tobe longer than the bottom pole tip 19 a, the contact area of the toppole tip 23 a and the top pole layer 25 can be made larger than a casewhere the top pole tip 23 a and the bottom pole tip 19 a are formed tobe the same length, and so that magnetic coupling can be better achievedin that area. Especially, this structure is effective when the top polelayer 25 is provided in a recessed position from the track surface(recessed structure), like the embodiment. In other words, if the toppole layer 25 is formed in a position which is closer to the tracksurface than the throat height =0 position (opposite edge frame of thetrack surface of the bottom pole tip 19 a), for example, the vicinity ofTH=0.5 μm, side write, which is writing information to adjacent track bythe top pole layer 25, occurs. Idealistically, the top pole layer 25 isbetter to be formed in a position further from the track surface than TH0 position. On the other hand, in the embodiment, the bottom pole tip 19a for determining TH is magnetically coupled to the top pole layer 25through the top pole tip 23 a. The top pole tip 23 a and the top polelayer 25 are required to be firmly connected in the opposite directionof the track surface from the TH 0 position. Accordingly, it ispreferable to form the top pole tip 23 a longer than the bottom pole tip19 a.

[0155] (2) By the way, the top pole tip 23 a and the bottom pole tip 19a are micronized and as the width becomes narrower, the contact area ofthe top pole and the bottom pole, that is, the width of the bottomconnecting portion 19 b and the top connecting portion 23 b becomenarrower. When the width of the bottom connecting portion 19 b and thetop connecting portion 23 b are micronized as described, and when theangle between the sidewall of the bottom connecting portion 19 b and thebottom magnetic layer 18, or the angle between the sidewall of the topconnecting portion 23 b and the top magnetic layer 25 are verticalrespectively, there is a problem that the magnetic flux may saturate inthat area. However, in the embodiment, the area of the top connectingportion 23 b is larger than that of the bottom connecting portion 19 band further, the bottom connecting portion 19 b is facing the centerarea of the top connecting portion 23 b so that, when looking at it incross section, the whole contact area takes a shape having a slope alongthe slope surface between the top and bottom coils, that is, the wholecontact area takes a shape as if it is a funnel. As a result, flow ofthe magnetic flux from the top pole to the bottom pole becomes smoothand magnetic coupling of both poles can be better achieved. Taper anglemay be provided in each of the top connecting portion 23 b and thebottom connecting portion 19 b, and with the structure like this, flowof the magnetic flux from the top pole to the bottom pole becomessmoother. Further, inversely, the area of the bottom connecting portion19 b may be formed larger than the area of the top connecting portion 23b.

[0156] (3) Further, in the embodiment, as shown in FIGS. 25A and 25B,the top pole tip 23 a which determines the track width is thinner thanthe top pole layer 25. As a result, even if much magnetic flux flowsfrom the top pole layer 25, the magnetic flux does not saturate in thatarea since the distance between the top pole layer 25 and the write gaplayer 22 is short. Accordingly, an over write characteristic and anonlinear transition (NLTS) is improved.

Tenth Embodiment

[0157]FIGS. 27A and 27B show the constitution of a composite thin filmmagnetic head according to a tenth embodiment of the invention. In theninth embodiment, a second layer of the thin film coil 24 is totallyburied under the surface of the top pole tip 23 a, that is, completelyinside the flattened insulating layer 20 d, however, when the top poletip 23 a is thin, the surface of the thin film coil 24 may be exposedduring the flattening procedure of such as CMP. In the embodiment, tomaintain insulating characteristic between the thin film coil 24 and thetop pole layer 25 in such a case, an insulating layer 30 of about, forexample, 1.0 μm in thickness, made of photoresist is selectively formedbetween the thin film coil 24 and the top pole layer 25. Otherstructures and operation effects are identical to those of the firstembodiment so that the description is to be omitted.

Eleventh Embodiment

[0158] In the embodiment, as shown in FIGS. 28A˜28C, the procedure untilforming the second layer of the thin film coil 24 is identical to theninth embodiment. After that, the thin film coil 24 is covered with aphotoresist film 31, then, the top pole layer 25 is formed on thephotoresist film 31 without having the top tip exposed to the tracksurface. FIG. 28C is a plan view of the bottom pole tip 19 a, the bottomconnecting portion 19 b, the top pole tip 23 a, the top connectingportion 23 b and the top pole layer 25 taken out from FIGS. 28A and 28B.

[0159] In the embodiment, unlike the ninth embodiment, flattening by CMPis not required to be performed after the second layer of the thin filmcoil 24 is formed. Accordingly, the manufacturing cost is decreasedcomparing to the ninth embodiment. The second layer of the thin filmcoil 24 with five turns is formed in a flat area of the first layer ofthe thin film coil 21 with six turns, so that the distance from theouter peripheral end of the thin film coil 24 to the throat height 0position does not affect the yoke length. Other structures and operationeffects are identical to those of the ninth embodiment so that thedescription is to be omitted.

[0160] The plan shape of the top pole tip 23 a and the top pole layer 25are not limited to the those shown in FIG. 28C, but may take a shapeshown in, for example, FIG. 29.

[0161] The invention also includes other various modifications, notlimiting to the embodiments. For example, in the embodiments, examplesof forming the top pole tip 23 a and the top pole layer 25 and so onwith NiFe (Ni: 50 weight percentage, Fe: 50 weight percentage), NiFe(Ni: 80 weight percentage, Fe: 20 weight percentage), and highsaturation flux density materials such as FeN, FeCoZr and so on aredescribed, however, a structure of stacking more than two kinds of thematerials may be possible.

[0162] Further, in the embodiments described above, the thin film coilto be buried in the concave formed adjacent to the bottom pole tip 19 ais a single layer, however, it may be a stacking structure in which twoor more layers of coils are buried.

[0163] Further, in the embodiments described above, the bottom pole tip19 a is formed to take a shape in which the sidewall is vertical to thebottom pole layer 18, however, as shown in FIG. 30, a slope surface(taper) 31 of about, for example, θ=50˜70°, according to the thicknessof the coil, may be provided in the sidewall. By having such astructure, saturation of the magnetic flux in the connecting portion ofthe bottom pole layer 18 and the bottom pole tip 19 a is suppressed andflow of the magnetic flux becomes smooth.

[0164] In addition, in the embodiments described above, a case where theinsulating layer 20 b and the insulating layer 20 d are formed withalumina, silicon dioxide or silicon nitride is described, however, aftercovering the thin film coil with, for example, alumina, the concave areaof the surface may be buried with SOG (Spin On Glass) film and may beflattened.

[0165] Further, in the embodiments described above, the first layer ofthe thin film coil is buried by the insulating layer in the concaveregion adjacent to the bottom pole tip 19 a, however, the whole concaveregion may be the inorganic-type insulating layer made of, for example,alumina. In the embodiments described above, a structure in which thebottom pole is made to correspond to the first magnetic layer and thetop pole is made to correspond to the second magnetic layer respectivelyis shown, however, a structure in which, each corresponds to the otherway around may also be possible. That is, a structure in which thebottom pole corresponds to the second magnetic layer and the top polecorresponds to the first magnetic layer respectively may be possible.

[0166] Further, in each embodiment described above, a manufacturingmethod of a composite thin film magnetic head is described. Theinvention may be applied to manufacturing of a thin film magnetic headfor recording only, having an inductive-type transducer element forwriting or of a thin film magnetic head for recording/reproducing.Further, the invention may be applied to manufacturing of a thin filmmagnetic head with a structure in which the order of stacking therecording element and reproducing element is reversed.

[0167] As described, according to the thin film head, or themanufacturing method of a thin film magnetic head of the invention, thefirst magnetic pole is formed to be divided from the first magneticlayer and to be convex shape on the first magnetic layer so that theinsulating layer made of an inorganic material can be buried in theconcave adjacent to the first magnetic pole. As a result, the throatheight is determined by the opposite side edge frame of the tracksurface of the first magnetic pole, so that a pattern shift of the edgeframe or deterioration of profile does not occur, unlike the photoresistfilm of a related art and precise control of the throat height can beachieved.

[0168] Further, by burying the thin film coil in the concave adjacent tothe first magnetic pole, a step of the apex area can be loweredcomparing to the structure of a related art. After that, in theprocedure forming the second magnetic layer by photolithography,difference in the thickness of the photoresist film in the top andbottom of the apex area is decreased and so that micronization of thesubmicron measurement of the second magnetic layer can be achieved. As aresult, high surface density recording by a recording head becomespossible, and performance of the recording head can be improved bystacking the coil to two layers or three layers.

[0169] Further, the second magnetic pole facing the first magnetic pole,is divided from the second magnetic layer and the second magnetic poleis formed longer than the first magnetic pole from the track surface toinside. As a result, the second magnetic pole can be micronized to thesubmicron measurement, while the contact area of the second magneticpole and the second magnetic pole is increased, flow of the magneticflux becomes smooth, precise control of the throat height can beachieved, and a thin film magnetic head with high precision can beachieved.

[0170] With the description made above, it is evident that variousembodiments or modifications of the invention can be achieved.Accordingly, within the scope of the appended claims, the invention maybe practiced otherwise than as specifically described.

What is claimed is:
 1. A method of manufacturing a thin film magnetichead having at least two magnetic layers including a first magnetic poleand a second magnetic pole being magnetically coupled to each other,part of sides of which facing a recording medium face each other througha write gap layer, and one or more than two layers of thin film coil forgenerating magnetic flux, including: a step of forming a first magneticpole on the first magnetic layer so as to be magnetically coupled topart of a region of the first magnetic layer after forming the firstmagnetic layer; a step of forming insulating layers with inorganicmaterials extendedly, at least from a surface of the first magnetic polewhich is the opposite of a side facing the recording medium to one ofthe surfaces of the first magnetic layer; and a step of forming a secondmagnetic layer including the second magnetic pole, at least, afterforming a write gap layer on the first magnetic pole.
 2. A method ofmanufacturing a thin film magnetic head according to claim 1 wherein atleast part of a film-thickness direction of, at least, one layer of thethin film coil is formed to be placed in a region where the insulatinglayers are formed.
 3. A method of manufacturing a thin film magnetichead according to claim 2 including a step of forming insulating layersextendedly from a surface of the first magnetic pole which is theopposite of a side facing the recording medium to one of the surfaces ofthe first magnetic layer, and a step of forming a second insulatinglayer, at least between windings of the thin film coil.
 4. A method ofmanufacturing a thin film magnetic head according to claim 3 including astep of flattening a surface of the second insulating layer which is theopposite of a neighboring surface of the first magnetic layer so as tobe substantially the same surface as a surface of the first magneticpole which is opposite of a neighboring surface of the write gap layer.5. A method of manufacturing a thin film magnetic head according toclaim 1 further including a step of forming the second magnetic layer soas to be magnetically coupled to, at least, part of the first magneticpole after forming the second magnetic pole on the write gap layer.
 6. Amethod of manufacturing a thin film magnetic head according to claim 5including: a step of forming the second magnetic pole to be longer thanthe first magnetic pole towards inside from a surface facing therecording medium, at least, after forming a write gap layer on the firstmagnetic pole; and a step of forming a second magnetic layer beingmagnetically coupled to the second magnetic pole.
 7. A method ofmanufacturing a thin film magnetic head according to claim 6 wherein thefirst magnetic pole is further formed, while the first connectingportion being formed adjacent to the first magnetic layer in thevicinity of the edge of the second magnetic layer which is on theopposite side of a side facing the recording medium; and the secondmagnetic pole is formed, while the second connecting portion having anarea different from the first connecting portion being formed adjacentto the second magnetic layer in the vicinity of the edge of the secondmagnetic layer, which is on the opposite side of the facing side of therecording medium.
 8. A method of manufacturing a thin film magnetic headaccording to claim 5 wherein the width of the first magnetic pole alonga surface which is facing the recording medium is formed to be widerthan that of the second magnetic pole.
 9. A method of manufacturing athin film magnetic head according to claim 3 wherein the whole part of afilm-thickness direction of the thin film coil is formed in a regionwhere the first insulating layer is formed.
 10. A method ofmanufacturing a thin film magnetic head according to claim 9 wherein:after flattening the second insulating layer, a write gap layer isformed on the second insulating layer; after forming the second magneticpole on the write gap layer, a third insulating layer is formed at leaston the write gap layer; then, at least one layer of thin film coil isformed on the third insulating layer on the write gap layer; and thethin film coil is covered with another insulating layer which isdifferent from the first to third insulating layers.
 11. A method ofmanufacturing a thin film magnetic head according to claim 10 wherein,after forming the other insulating layer with inorganic materials, theother insulating layer is flattened so that its surface forms the samesurface as the surface of the second magnetic pole and, then, the secondmagnetic layer is formed on the second magnetic pole and the otherinsulating layer being flattened.
 12. A method of manufacturing a thinfilm magnetic head according to claim 10 wherein, after selectivelyforming the other insulating layer with organic materials, the secondmagnetic layer is formed on the second magnetic pole and the otherinsulating layer.
 13. A method of manufacturing a thin film magnetichead according to claim 1 wherein a surface of the second magnetic layerwhich is on the opposite side of a facing surface of the write gap layeris formed to be flat.
 14. A method of manufacturing a thin film magnetichead according to claim 1 wherein the thin film coil is buried in aregion where the insulating layers are formed, and a surface of thesecond magnetic layer, which is on the opposite side of a facing surfaceof the write gap layer, is flattened.
 15. A method of manufacturing athin film magnetic head according to claim 1 further including a step offorming a magnetoresistive element for reading out.